Author: stilesm

This post was originally published September 2, 2021. Posts have been manually reordered for more logical storytelling. To go to the next post in the sequence, click “Previous Post” at bottom.

Just a few short decades ago, in the mid-1970s, the number of recognized species of whales, dolphins, and porpoises worldwide was 76. Today, there are 93. Some are so poorly known that they have never been identified alive in the wild (they are known only from stranded specimens). All of these belong to a single genus of beaked whale: Mesoplodon.

Currently, there are 16 known species of Mesoplodon — including five added since the mid-1970s. Six of these have never been identified alive in the sea: M. perrini, M. hotaula, M. hectori, M. traversi, M. bowdoini, and M. ginkgodens — and one or more could live in Oregon waters. Although small by whale standards (4–6.2 m), mesoplodonts can still weigh well over one ton (900 kg), placing them among the largest 0.001% of animals on Earth.

In 2014, during a research trip investigating the Eastern Garbage Patch (EGP, roughly halfway from Oregon to Hawaii), marine biologists photographed two separate groups of small, unidentified whales. Adult male mesoplodonts have species-specific dentition (a pair of erupted teeth that they use as tusks to vie for females), and the whales in the photographs appeared to be either M. ginkgodens, M. hotaula, or possibly a new species.

In September 2021, scientists from the Oregon State University’s Marine Mammal Institute (MMI) and the National Oceanic and Atmospheric Administration (NOAA) are mounting a month-long expedition on the R/V Pacific Storm to search for this cryptic whale. Among the accumulated plastic debris and abandoned fishing gear of the EGP, they hope to find one of the largest, least known animals on the planet.

But why does this matter?

Human enterprise has made the ocean an extremely noisy place, from seismic testing used for science and oil exploration, to military use of high-intensity sonar to detect submarines. These sound sources have resulted in the deaths of untold numbers of beaked whales, apparently because a fright response causes individuals in deep water to bolt to the surface, which can result in bends-like symptoms and death.

Currently, mesoplodont beaked whales are among the least known whales in the world — we know very little about their numbers and distributions, or even how many species there are. The ability to identify them to the species level using their recorded acoustic signals could make it possible to survey these elusive animals using passive acoustic methods. That could be accomplished, for example, by attaching hydrophones and recorders to commercial vessels traveling across oceans within shipping lane “highways.”

This Gyre Expedition hopes to provide essential information to better understand the population status of beaked whales around the world and to assess their vulnerabilities to anthropogenic (human-caused) sounds.

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The Beaked Whale Expedition to the Eastern Pacific Gyre is a collaboration among Oregon State University’s Marine Mammal Institute, NOAA Southwest Fisheries Science Center’s Marine Mammal and Turtle Division, and NOAA Northeast Fisheries Science Center’s Protected Species Branch. It is made possible with seed funding from the MMI gray whale license plate program. The expedition is led by Principal Investigator Lisa T. Ballance (MMI), co-PI Robert Pitman (MMI), co-PI Jay Barlow (NOAA), and MMI collaborators Scott Baker, Daniel Palacios, and Leigh Torres.

(This post was originally published September 7, 2021. Posts have been manually reordered for more logical storytelling. To go to the next post in the sequence, click “Previous Post” at bottom.)

The term “cetacean(s)” refers to all whales, dolphins, and porpoises. During this expedition, we are searching for beaked whales in the genus Mesoplodon (accent on the second syllable). Although small by whale standards, mesoplodonts can weigh 1–1.5 tons, which still makes them among the largest animals on earth. Currently, there are 16 recognized species of Mesoplodon, and surely more yet undescribed. Most of what we know about this group comes from dead specimens stranded on beaches, and by my count, 6 species have never been identified alive in the wild.

Mesoplodonts live in open ocean waters and dive 1000–2000 meters for up to 1.5 hours at a time, mostly searching for small squids and midwater fishes. They are not very social. Group size is typically 2–3, usually a mother and calf, sometimes with a suitor. For the most part, they come to the surface only for a few quick gulps of air before descending back into the cold, dark depths that they inhabit most of the time.

Their main enemies are killer whales that patrol the surface waters. Beaked whales vocalize at depth, to communicate with each other and to echolocate their prey, but as they return to the surface, they observe radio silence so as not to tip-off any eaves-dropping orcas. Mesoplodonts are rarely seen at the surface: they seem wary of any strange sounds and usually slip under the waves at the approach of a vessel.

The name Mesoplodon roughly translates to “armed with a middle tooth.” Mesoplodonts are suction feeders that do not require teeth for feeding; females remain toothless their entire lives. Among maturing males, however, a single pair of teeth erupts from the lower jaw at various locations, depending on the species. Males use these teeth to spar with each other to determine access to breeding females. Instead of having horns or antlers for fighting, mesoplodonts use their out-sized teeth, which grow above the level of upper jaw. Although these battles have never been witnessed, they must be fierce, because when jousting males rake each other with their tusks, they sometimes leave deep, bleeding furrows along each other’s bodies.

In one of these species, the male has a tooth shaped like the leaf of a ginkgo tree — Mesoplodon ginkgodens (see photo in our first blog post). It is one of the species that has never been identified alive in the wild, and we suspect that it, or something like it, occurs in the Eastern Pacific Gyre. Our little expedition (GyreX) has come looking for it.

~ Bob Pitman

(Posts have been manually reordered for more logical storytelling. To go to the next post in the sequence, click “Previous Post” at bottom.)

Special report from the R/V Pacific Storm, September 7, 2021:

Early this morning, we encountered transmission troubles. We were able to get the transmission into manual override forward. All are safe on board — but because we are so far from land, we have made the decision to go back to Newport rather than further diagnose the transmission problem out at sea.

This is the nature of ships and science at sea. Meanwhile, the weather is spectacular and the forecast is good. We intend to carry on with our science, as best we can, on the way in. We are in full acoustic and visual survey mode and are recording marine mammal detections (visually and acoustically) — including two beaked whale sightings!

Earlier today, we plucked a large, dead squid from the water, which a Black-footed Albatross was feeding on, and obtained a sample. (Squids are the food of choice for beaked whales.) Meanwhile, we have great meals ourselves, hot showers, and are enjoying the natural world surrounding us. It is times like these that bring the character of your shipmates to the surface. I am surrounded by the best of the best out here.

~Lisa Ballance

(This post was originally published September 16, 2021. Posts have been manually reordered for more logical storytelling. To go to the next post in the sequence, click “Previous Post” at bottom.)

We are repaired! The Pacific Storm is back — thanks to our awesome crew and their expertise. With half of September gone, we do not have adequate time to reach the gyre, conduct our research, and return home by the end of the month (the round-trip transit alone requires the better part of two weeks) — but there are beaked whale mysteries to investigate right here in the seas off Oregon (and seaward to 200 miles where we would like to work). So, we are anxious to resume our research.

Unfortunately, the weather seems to have other plans. Winds at our hoped-for destination will be 25 miles/hr by midday Friday, with seas at 7 feet and increasing to 12 feet by Sunday. Of course, this could change, and we will be watching the weather constantly and continuously.

But we need to make a plan now. So this morning (Thursday), we left Newport at first light and are sailing due west to a point 60 miles offshore, where we will deploy two passive acoustic recorders. (More on these later.) Immediately afterward, we will head back to Newport, arriving late in the evening that same day, to shelter from the storm.

In a few days, we hope to sail again in calmer seas to retrieve these buoys and look for more mysteries. Watch this space!

~Lisa T. Ballance

(This post was originally published September 20, 2021. Posts have been manually reordered for more logical storytelling. To go to the next post in the sequence, click “Previous Post” at bottom.)

“I have small puffy blows here,” Ladd casually remarks while scanning the ocean horizon with our high-powered “bigeye” binoculars. Intrigued, I immediately swing my own pair of the heavy binoculars over to his patch of water. Like whalers of old, modern trained observers often can tell the species of whale seen at a distance by the size and shape of its blow. Judging by the cluster of round-shaped blows erupting above the calm water like exploding fireworks two miles out in front of the ship, I knew we were seeing something special. 

“Baird’s beaked whales!” I shout, barely able to contain my excitement. Baird’s beaked whales are named after the Smithsonian Institution’s first curator, Spencer Fullerton Baird, and they are the largest member of the beaked whale family, reaching lengths of nearly 40 feet and weights of 13 tons. They are rarely observed at sea.

Judging by the constant blows, we estimate that there are at least 12 whales packed tightly together at the surface. After only a minute or so, the blows suddenly stop, and the whales disappear. From our vantage point 30 feet up in the crow’s nest, we radio down to the acoustic team monitoring the underwater hydrophone being towed a hundred meters behind the Pacific Storm. “Baird’s beaked whales! Twenty degrees right and 2.3 nautical miles from the ship.” A moment of disbelief on the other end is followed by, “That’s great! We’re on it.” 

Like bats, beaked whales produce high-frequency clicks while foraging. We know from a high-tech digital acoustic tag placed on a Baird’s beaked whale off California nearly ten years ago that the species makes a series of shallow dives (if you can call diving to 400 meters “shallow”) followed by an extended, deeper foraging dive to over 1,000 meters, which can last as long as an hour and a half. It is typically only during deeper dives that Baird’s beaked whales produce their characteristic clicks as they search for prey. 

After ten minutes, the acoustic team radios back up to us and states that they are not hearing anything on the hydrophone, suggesting that the whales are making a silent, shallow dive. Ladd and I continue to scan the ocean, joined now by several other members of the science team and crew, each of us eager to spot these unusual whales again. 

A half an hour passes and still no sign of the whales.  There is a reason beaked whales are among the least known species of mammals on the planet. Finally, 33 minutes after last seeing the whales at the surface, we spot their distinctive blows again, one mile directly ahead of the ship. Two minutes later, the blows suddenly stop and the whales disappear once again. Acoustics radios up soon after and states that they are still not hearing them. Another shallow dive.

The whales seem to be moving steadily to the north, and this time we position the Pacific Storm a mile in that direction. After 23 minutes, the whales surface once again, this time just a few hundred meters away. We all scramble for our cameras as the whales provide us with an extraordinary view of their backs and heads. Gigabytes of photos are taken as well as nearly four minutes of video footage. After five minutes at the surface, the whales arch their backs high out of the water and make an obvious steep dive, powering down into the depths. 

A few minutes later, the acoustic team excitedly radios up, “We have clicks!” The Pacific Storm stays in the area for over an hour, through an entire foraging dive, and more than 31 minutes of high frequency clicks are recorded.   

As is so often the case with beaked whales, we are unable to relocate the whales after they surface from their deep dive. Nevertheless, the encounter has provided us with an abundance of visual and acoustic data that will help shed some light on the mysterious lives of these incredible animals.

~Todd Pusser

(This post was originally published September 24, 2021. Posts have been manually reordered for more logical storytelling. To go to the next post in the sequence, click “Previous Post” at bottom.)

Think of a command center — a single person monitoring many screens all around them. This is what we acousticians call home while at sea. On the Gyre Expedition, we listen to sounds in the ocean in real time, detected by a long cable containing underwater microphones (known as hydrophones) towed behind the research vessel Pacific Storm. We use a variety of software tools to visualize these sounds, because our human sense of vision is much better than our sense of hearing (unlike the beaked whales and other marine mammals we study).

Sound is measured on a frequency scale, and our hearing has evolved to be sensitive to frequencies important to us. As we age (starting as early as 20 years old), our hearing deteriorates over time, especially for very high frequency sounds. Do you live in a rural area with very little background noise? Do you wear earbuds often? Are you a construction worker listening to the constant sounds of engines and machinery? Our individual experiences and interactions with sound in our daily lives make our hearing capabilities unique to each of us.

Most marine mammals vocalize outside of the human hearing range. This is why we need so many displays — to see this “ultrasonic” sound. Each display provides specific information about these vocalizations, maps indicating the location of the sounds, and forms for recording additional data.

Listening to beaked whales from our “command center” reminds me of playing whack-a-mole. Our primary display consists of little dots, each representing a click, which scroll by telling us about the time and location of the animal that produced them. Clicking on each dot produces three diagnostic plots that provide more information, as seen below. These dots flash by and are typically visible for about one minute as new clicks continue to stream in.

There is still much to learn about species-specific characteristics of beaked whale vocalizations. This expedition is providing us data to add to a growing library of knowledge, ultimately with a goal of identifying beaked whale species based solely on the sounds they make. The recent Baird’s encounter was one such fortunate event where the whales dove within two to three football fields of us and stayed nearby, allowing us to capture thousands of clicks to study. A very rare treat!

~Annamaria DeAngelis

(This post was originally published September 29, 2021. Posts have been manually reordered for more logical storytelling. To go to the next post in the sequence, click “Previous Post” at bottom.)

It is a privilege to study marine mammals, but it also takes us away from home — at times, to remote and distant places or for long periods of time. Three members of our expedition have children younger than five. What is it like for these scientists to be away from their son or daughter for an entire month?